Document validation, done automatically
Invoice and document validation has traditionally been a manual job: an accountant re-typing figures into a calculator, checking that an invoice adds up, confirming a VAT number looks right. It doesn't scale, and it's exactly the kind of repetitive, rules-based work software does better. The validation engine automates it — running the same rigorous checks on every document, in seconds, whether you process five invoices a month or fifty thousand. It's the layer that separates cheap PDF converters from serious B2B platforms like Rossum, Nanonets and Klippa.
Why deterministic checks matter
Arithmetic should never be left to a language model. The validation engine re-derives every figure precisely: line totals from quantity and price, VAT from the taxable amount and rate, and the grand total from the subtotal and VAT. Because these checks are deterministic, a flagged error is a genuine error — not a guess. The results of line item extraction and VAT extraction are only as useful as their accuracy, and validation is what guarantees it.
Built into the workflow
Validation isn't a separate step you have to remember — it runs automatically as part of extraction, and its findings appear in the editable preview where you can fix any flagged value and watch the checks recompute. For VAT-specific compliance, the AI VAT Auditor builds on the same engine to produce a full audit score. When everything reconciles, export clean data with invoice PDF to Excel, validate a single document instantly with the invoice VAT checker, or process transactions from a bank statement to Excel.